Two main types of snow blowers exist on the market, those being single-stage and two-stage snow blowers. The single-stage snow blower is characterized by an auger mounted transversely that conveys the snow to its center where a rotor that is integrated onto said auger, projects the snow through a vertical duct. The mechanism of a single-stage snow blower is illustrated in FIGS. 1 and 1a, identified as "EXISTING ART". Arrows "A" indicate the movement of the snow that is conveyed by the auger and its centrally integrated rotor; arrow "T" indicates the direction of motion of the snow blower; and arrow "N" indicates the direction of the snow that enters into the snow blower. The shortcoming of this type of snow blower is the high speed of rotation of the auger/rotor combination that is required to eject the snow.
The two-stage snow blower incorporates a second stage that is added to a first stage, which is identical to the one described for a single-stage snow blower. The second stage adds a second direction of movement to the snow following the movement initiated by the first stage. This second stage consists of an impeller mechanism that propels the snow with force out of the snow blower. FIG. 2, also identified as "EXISTING ART", illustrates the mechanism of a two-stage snow blower. Arrow "A" indicates the initial displacement of the snow by the first stage, and arrow "B", the displacement of the snow by the second stage. The second stage facilitates the ejection of the snow and allows the use of an auger turning at a moderate speed. Advantageously, the optimum speed ratio of auger and impeller are easier to control.
However, both types of snow blowers described thus far have a common shortcoming, and that is that they can only work while travelling in one direction i.e. forwardly. In many circumstances, such as residential driveways and commercial parking lots, operators must travel backwards repetitively in order to re-position the equipment to blow snow in a forward movement. Each time the operator must back up, the snow blower is unproductive. A snow blower rendered functional moving backwards would increase its profitability by greatly reducing its idle time. Furthermore, as the snow blower travels forward, it tends to push a certain amount of snow in front of it, (represented by the letter "M" in FIG. 2) which is left in front of any obstacle where the snow blower must stop and back up. Hence, another type of equipment such as a plow blade or a shovel must be used to remove the snow that has been left behind.